The present invention relates to epoxy resin based compositions and their use in adhesive applications.
Adhesive compositions prepared from epoxy resins exhibit a number of advantages including good strength, adhesion, corrosion resistance and suitability for formulation at high solids levels. One marked disadvantage is that epoxy based adhesives deform the substrates to which they bond because of shrinkage during cure.
In structural adhesive applications this deformation is of particular concern, especially in the automobile industry wherein the appearance of the substrate is of critical importance. This substrate deformation is not only unsightly, but it also necessitates the expenditure of additional costs in labor and materials in order to restore the intended appearance of the substrate.
There is a need, therefore, for a curable epoxy based composition which, when formulated into an adhesive, exhibits excellent physical properties but has markedly reduced shrinkage.